This webpage reproduces an article in
Memoirs of the American Academy in Rome
Vol. 4 (1924), pp169‑180.

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p169
The Date of the Arch of Constantine

In a series of articles1 on the Arch of Constantine in Rome, Professor Frothingham has put forth the view that it was already built before the time of Constantine, and in fact was one of many arches constructed for Domitian. He further thinks that it was remade and redecorated in honor of certain emperors of the third century, and finally was reinscribed and otherwise adapted to commemorate the greatness of Constantine.

There are some points of construction however which show that the main hypothesis is not correct, although the contention may well stand that the arch was built before Constantine. If a date is assumed in the latter half of the third century, the arguments against the Constantinian date hold good, while there is nothing in the construction itself which would do violence to such an inference. As Mr. Frothingham has not yet published his observations on the architectural details of the arch, the inference may be drawn that he found nothing in them to combat his theory. As a matter of fact, the chief grounds for contesting his thesis are architectural, and these facts seem irreconcilable with any theory which places the arch before the third century.

The evidence of the relief from the monument of the Haterii in the Lateran Museum,2 as will be seen, does not bear on the problem at all. The date of the relief is usually considered Domitianic, but there is a difference of opinion on this point,3 and it may be not earlier than 132 A.D. Mr. Frothingham explains the arch which is represented between the Colosseum and the Arch of Titus as a triple arch which stood in the time of Domitian where now stands the Arch of Constantine, and thinks that it is shown in
p170 profile. He compares it with a photograph of the arch taken from the west, and apparently concludes that the free-standing columns of the arch are represented on the relief.4 He further holds that free-standing columns may well have existed on an arch before the time of Hadrian,5 and states that he has found them represented on coins of Domitian.6

Now if the arch is shown in profile, it is surely drawn with free-standing columns. And it would be difficult to prove that they may not have existed on arches at the time of Domitian, even if there are no extant examples. The free-standing column was used during the first century on a flat wall, as is well known from contemporary paintings with architectural details, and from the interior of the cella of the Temple of Concord in the Forum, and they were applied to embellish the precinct wall of the Forum Transitorium of Nerva. There is no reason why the same decorative device may not have been used at this time also on arches.

But in Mr. Frothingham's fourth paper,7 he expressly says, "at the first restoration of the arch when the columns were added, the main cornice restored and the resaults added to it above the columns". If the columns were added in some restoration in the third century, as he holds, how could they have appeared on the relief?

Again, an image of Cybele is represented in a vaulted opening in what is called the end of the arch, in a niche especially hollowed out to receive it, together with an approach of thirteen steps and an altar in front. The deity is thought to have stepped from her shrine on the Clivus Palatinus8 to do honor to the Haterii. This niche and the image, which, if the arch is drawn in profile, are free inventions of the sculptor, are drawn in the same manner as the vaults and images in the other two arches on the relief which are in full view. Not only is the opening cut with unbroken and regular vaulting, but also with details of impost cornice and keystone. In fact the depth is greater, and the cutting sharper in the arch in question. So we see, not the end, but a face of an arch. Any other inference arbitrarily involves ignoring the architectural details which we accept in the case of the other arches on the relief. Furthermore, if the arch is drawn in profile, it is drawn as it appears who is coming from the Arch of Titus. As a matter of fact, the backgrounds of historical reliefs represent buildings in sequence, not from one point of view. If "the smaller size and lower relief show its distance from the Arch of Titus", we have an instance quite unprecedented of the use of linear perspective in the Flavian period. Moreover, if the relief shows buildings absolutely from
p171 one point of view, the Arcus ad Isis stood near the Colosseum. Now the temple of Isis of Regio III stood near the site of the church of SS. Pietro e Marcellino, far beyond the Colosseum,9 and an arch named from its position in relation to that monument could not have been seen at all from the Arch of Titus. If on the other hand, some arch nearer was drawn, and the sculptor understood and used linear perspective, the unidentified Arcus ad Isis must have towered above a Lilliputian col. Surely the smaller scale of the Colosseum is not the result of an attempt at foreshortening, but an instance of a common device of classical painting and sculpture in relief by which a part symbolizes the whole, so that the arches of the colonnades are reduced in number, not in scale. That the triumphal chariot is shown in profile, extending to both ends of the arch, would disturb the conclusion that the arch is seen from the front, were it not that similar drawings are seen occasionally on coins.10 A Tethrippos hides the Emperor quite effectively, which is a sufficient reason for the designer to represent the chariot in profile, or omit it entirely from the top of the arch. The difficulty of the problem is evident enough in the chariot of the inner frieze of the Arch of Titus, where the chariot and horses are proceeding at right angles to each other, or on a coin11 of a triple arch of Augustus, where one horse is in profile and there is no chariot, but a dimv emperor above the heads of the horses, or on a similar single arch of the same Emperor.12

The evidence of the relief then may be disregarded as bearing out the thesis. If an arch is represented which stood between the Arch of Titus and Colosseum, it was single, with eight attached columns.13

The main argument of Mr. Frothingham rests on the sculptured and architectural members which date from the Flavian period, which he considers a part of the original arch in its present position. The argument turns on the assumed Flavian date of the eight medallions of north and south sides.

The Flavian date of these tondi is by no means assured. Arndt14 and Reinach15 consider them of the time of Hadrian: Petersen16 and Studniczka,17 as of Trajan, though the latter sees in those of the north side much to remind him of the reliefs of Hadrian; and to Bulle,18 the work of Miss Bieber19 has definitely settled their date as of Hadrian,
p172 while Sieveking20 comes to the same conclusion, though by a different course of reasoning. Stuart Jones, in 1906,21 followed by Mrs. Strong in 1907,22 made a plea for their Flavian origin. In the face of expert disagreement, not in the facts, but in the deductions from them, it would be rash indeed to be dogmatic about their date.

Mr. Frothingham interestingly points out that the medallions were originally nearly circular, flattened somewhat at the base, with a squared projecting base resting on the course below, and that the higher surrounding courses were given a curved outline to fit the circumferences of the tondi. Later the surface of these course blocks was in large part cut back to admit a veneer of porphyry which formed a rectangular frame around the medallions. Now it is inconceivable that this veneer was placed around the tondi when they were first used as decorative members whether in the time of Domitian, Trajan or Hadrian. It is especially impossible here, that the original masonry was so covered, for the frame of veneer cut off a portion of the circumference of the tondi at the base, which made it necessary to cut back to some extent the raised fillet frames, which surround the tondi. Originally, therefore, the tondi were probably set in masonry in courses flush with them, just allowing for the projection of the fillet frames. If we have before us on the arch the masonry as it first surrounded the tondi, the joints of the courses indicate the lines of the masonry (making due allowance for repairs), as they were visible in the second century. But the horizon lines are very irregular. Take, for example, the most regular courses around tondi North 1 and 2, counting from left to right.23 The lowest course in the center is higher than the three above it. All the course blocks differ in height, and no horizon joint is in line with any other. The blocks around the tondi of the south side are even more irregular, as was noted by Mr. Frothingham, although he apparently did not relax that the present surfacing" which is a
potpourri of rough and smooth masonry with occasional wide joints" indicates a surface which, according to his theory, was visible before the veneering was let back into it, and that the south side shows even more conclusively than the north side that the porphyry was set over badly jointed blocks to cover their irregularity. No special value as evidence of their original position can be put on the unusual height of the lowest course in the center. As a matter of fact, beyond the pilasters near the ends of the arch, the courses do not continue at this height. Such irregularity of the surrounding masonry is to my mind conclusive proof that the tondi are neither in their original position, nor surrounded
p173 by the same blocks as when first placed. The builders covered their clumsy resetting by a veneer.24

A word may be said as to the position of tondi as a decorative element. Any frame which is out of harmony with the main lines of the monument on which it is placed becomes the centre of interest because of its very discord. It is then to this point that the eye is most naturally drawn. For this reason, portraits in form of clipei on grave reliefs are more conspicuous when left unframed. When the Romans used the motif of the tondi, whether representing real clipei, or as frames, they emphasized still further this property by isolating them between columns or pilasters or supporting them by contributing motives. Now the effect of placing more than one circle between two columns as we find them on this arch is to distract the attention, an error which seems not to have been committed in the Flavian period. As it has been shown that they were not set originally as at present, it is probable from the evidence of other tondi on arches25 and reliefs26 that the eight medallions were once separated by a series of pilasters or attached columns, and that we must think of them on some monument which was either faced with a flat wall in imitation of a colonnade with the tondi between the attached columns, or in the spandrels between the arches, or on corresponding positions on a colonnade. As they are now set they are too close together for the effective composition of the arch or for the display of their details. Again, if they were placed in their present position before the friezes were planned to be set below them, why were they placed somewhat higher than the center of the space between the keystone and the architrave? Below them there are two courses of normal height while above there is only one between them and the architrave.

The construction of the projecting pedestals, the columns and the entablature furnishes more direct evidence against the Flavian date. The material of the columns and pilasters with their capitals is different from that to bases and plinths and the surrounding masonry. It is giallo antico except for N. 4, where a white column was substituted for one which was taken in 1597 under Clement VIII to the Lateran to be placed under the organ.27 The blocks on which the capitals of the pilasters are carved extend into the courses of the main construction but without accurate fitting of the vertical joint, which indicates that they were not made especially for this arch, even if the difference of material were not unprecedented in an arch of the Flavian period. Mr. Frothingham
p174 himself did not believe them original as has already been stated. The bases and pedestals however are original. The square plinth of each column base28 rests on a course which included the crown moulding of the pedestal and a cut-back portion above with which it is flush on face and sides.29 This pedestal course is this formed of two blocks, one of which serves as plinth for the column, while the other runs back into the main construction of the arch. It is carved in such a way that both its upper cut-back portion and the lower section which forms the crown moulding of the pedestal line up with a corresponding course of the arch, but the blocks on which they are carved are dove-tailed into the pier of the arch in such a fashion that the upper portion continues on the pier for some distance before there is a break, while the projecting crown moulding of the pedestal stops dead against a corresponding string course. The mouldings on the base of the pedestals are also continued as string courses around the base of the piers. The pedestals then were set in place at the time of the building of the main portion of the arch. Therefore, whatever the period of the arch, from Domitian to Constantine, it had free-standing columns supported by the very pedestals now in existence.

The frieze is rough and without decoration. It would be difficult to say what was intended to be placed there, whether a veneering of colored material like that around the medallions, or thin carved blocks. No traces are apparent of any covering and it seems probable that the arch was never finished here.

Above this frieze is the main cornice which, according to the Domitianic theory, is of the Flavian period and belongs to the first building. As the original arch is proved by the bases of the columns and pilasters to have had projecting pedestals and free-standing columns, this cornice would be expected to crown the entablature of these members, but in no case is the cornice of the projecting entablature of the same style as that of the entablature between the columns. The most striking evidence for this is seen in the treatment of the dentils. Between the sixth and seventh dentils on the west end, counting from the south corner, and also between the seventh century and the eighth may be seen two rings in each space still intact, and the next spaces show them only slightly broken. Everywhere along the fine cornice the broken points of rings may be traced. Another less usual feature occurs which had the same purpose, namely, to break up the sharp contrast of masses of light and shade given by dentils in a strong light. The thin plate which is left between the dentils parallel with their faces is set a little back from their surface, and a cutting is made which runs up behind the horizon fillet above it. This is the plate which is perforated to leave rings and a semicircular space above them. In this way
p175 a shadow is cast above the ringplate under the fillet, and the death of the dentils brings out in relief the rings and the semicircle above.30 The cornice over the columns nowhere has such ringplates. Between the dentils, which appear to have the same proportions as those of the face and end cornices, are very thick ringplates, flush with the face of the dentils. Across the front of the projections these are perforated in a kidney shape, evidently in an attempt to imitate the delicate work of the main cornice. On the sides of many of the projections the clumsy ringplates are merely incised for cutting; on some they are left entirely uncut, as on the west side of projections N2, S2, S2, S4, and on the east side of N3, N4, S1, S2. Further bad design is evident in the variety of the finish at the corners. They are finished with a dentil in N1, N4, S1, S3 and S4. N3 and S2 have pomegranates, and N2 has the pigna. The evidence of the other imitated motives of the projections is equally convincing, though less striking.

If we did not have evidence that the pedestals were a part of the first construction, we could easily explain the difference of style here as showing the later addition of free columns, and expect to see the fine main cornice continue all round the arch except where it meets the projections. But here again the evidence fails. In all cases except those nearest the four corners of the arch, the reentrant angle of the projection is formed by a block of the inferior style, which, after a few dentils in both directions, is broken off in lines which in some cases run at varying angles up through the egg and dar pattern into the consoles. This irregularity led in every case to a hopeless jumble of patterns at the corners. Had the main cornice once been continuous around the arch, it would have been cut with greater economy at the corners where a projection was to be added, either mitered at the corner, or sharply vertical if away from the corner. Now the mitering occurs only at the outer projections nearest the corners of the arch, just at the points, it will be seen, where the builders had enough of the main cornice connected with a corner block to form the return. We must believe from the evidence of the pedestals that the projections formed a part of the original plan of the arch, so it is clear that when it was first built it presented the same confusion of cornice blocks as now. The builders used the main cornice as far as it would go, and were obliged not only to imitate it over the columns, but to piece it out on both sides of each projection, except near the four corners.

The strong est proof of all, however, is found on the cornice block at the southwest corner. Two original corner blocks are preserved on the arch. These are at the northeast and the northwest. The fine cornice starts from the east corner of projection N1 with
p176 a correct mitering and runs with seven dentils to the corner and then across the east end of the arch for thirty-five dentils, then follows a short block of six dentils. Beyond this to the angle of the projection S4 is a block with five dentils on the east side, in such an excellent state of preservation, in contrast to the adjoining block on the east, that it is thought to be a specially good bit of restoration, replacing, according to Petersen,31 an antique block of the same style. This block is also mitered at the corner of S4. The second original block of this fine style starts at the west corner of N4, runs for seven and a half dentils to the corner of the arch, then for forty four and a half dentils with two breaks across the west end. The southwest corner is also a single block, extending from the corner of projection S1 through sixteen dentils of the northwest end. This corner shows, however, both styles, the fine sharp work on the west end, and the heavy ringplates left uncut on the south side, where the shallow carving of the egg-and‑dart and of the rosette between consoles is also noticeable, and where the dentils are far less deep from back to front. Moreover, the consoles at the corner do not touch at their bases so as to enclose a square for the rosette, but the rosette field is oblong, and across its narrow end toward the south can be seen traces of a console which was chiselled off, while in the egg and dart pattern a sharp undercutting follows the line where an egg was cut out. The block which was used for this corner was clearly longer than at present. The builders of the arch cut it off to make it the right length, and then carved its end with a return moulding in imitation of the rest.32 This block is mitered at projection S1, which was the practice of the builder when he had enough of the cornice to reach to the projections.

The confusion of patterns at the angles of the projections and treatment of the southwest corner is in itself sufficient evidence that the whole cornice is a mass of patchwork, and even where the fine cornice is continuous, the short blocks, as noted by Petersen,33 and the manner in which some of them are set show that they were taken from another building. For example, on the south side, over the main arch, there is no space between dentils number 17 and 18. The fifteenth dentil on the west end is made of two half dentils, which may not be conclusive, but of the twenty-ninth of this end, only one half is present.

No special stress can be laid on the delapidation of the main cornice as the result of taking down the quadriga of Domitian, for the accidents during sieges of Rome are sufficient to account for its present condition. The robbery of not only parts of the sculptures but of the very material of the arch was fast reducing the latter to a ruin by
p177 the middle of the sixteenth century. In 1570, attention was called to its condition, and it was put in repair. As most of the damage was due to the fact that the clamps which held the sculptures were loosening, and that trees were growing out from behind them, these repairs must have been mainly on the attic.34 Further extensive restorations were made under Clement XII (1730‑1740). The plain cornice of the attic owes its state of preservation to one of these restorations, and the south-east corner of the main cornice may well have been inserted at the same time.

The character of the spandrels deserves attention. The voussoirs of the side arches are all irregularly cutting beyond the outer fillet of the archivolt, and the spandrel block with horizontal course lines are fitted against the voussoirs. The moulding below the friezes is in every case carved in the upper course of these blacks, and in the case of N1,35 the block which carries the moulding extends into the frieze itself. This has been explained as strengthening the cornice over the keystone.36 But this would have been no less necessary over the other three keystones. It is more likely that this block was set in at some time of restoration, as the keystone below shows greater damage than those of the other arches. Now, on the Flavian theory, the spandrels were taken out for the sake of inserting this moulding, and other blocks were fitted over the archivolt, and the designs carved upon them. If these spaces were originally undecorated, it would have been easier to cut out only the upper course and substitute one which carried a moulding, or even to cut out a horizontal band from the top of the upper course, and insert a moulding. If on the other hand, as is customary in an arch of the Flavian period, the spandrel spaces were decorate days with reliefs, their designs were unpolitical and general in character, such as Victories, winds, or local divinities. It is difficult to see why the rebuilders went to the trouble of removing the spandrel blacks and substituting others which were to be carved with the same sort of innocuous design. It is further to be noted that whether this space is slight plain or decorated, it would be capped by a moulding which would serve admirably for the base of any frieze which might subsequently be put on top of it. In brief, if ours were a remade arch, these fields would not have been changed. From the second of the side archivolts, there is no doubt that they came from an unidentified arch. For some reason, the builders of our arch did not see fit to take also the spandrel blocks, but set in clumsily those which now appear.

The case of the spandrels over the main arch is quite different. The nineteen courses of the centre vaulting are continuous with the nineteen voussoirs so that they are apparently built in at the same time. The voussoir blocks are continued into the field of the spandrels, but do not form horizontal courses according to the normal method,
p178 and in fact are current irregularly at various angles. The quality of the bead and reel ornament of the archivolt is poor, so it is reasonable to conclude that all of the central arch, including the archivolt and the spandrel field and moulding is of one period, that of the spandrels, and not earlier than the middle of third century.

The carved panels under the main arch and those at the east and west ends of the attic once formed a continuous frieze, and come from some monument of Trajan. The length of this frieze, estimated to have been originally about twenty metres, precludes the possibility that it was taken from any arch, or made expressly for this one. The four portions were all placed at the same time, that is, when the attic was constructed, not earlier than the middle of the third century.37 The panel under the main arch, on the west side, with its including fillets at top and bottom exactly fits the five horizontal courses of masonry, but the course above the east panel was cut a very little to fit over it. The masonry of the entire vault is accurately set. The correspond of the courses to the height of the reliefs makes it improbable that the latter were inserted in a wall which previously existed. More likely the height of the course was chosen to correspond to that of the reliefs. If this was not the case, then this important space was left undecorated at the assumed first construction of the arch. Moreover, the surface of the ends of the blocks which are cut back at right angles to bound the west relief on the right, is smoothly finished, as was natural if, when they were set, the space was planned for the insertion of the slabs. But on the left of the west relief, the calculation went astray. Part of the standard carried behind the mounted Emperor was sawed away when the relief was cut for its present position, and its lines were continued out on the masonry of the arch. Here the work is only blacked out.38 As the lower part of the figure carrying the standard was cut away, the blocks of masonry were hacked obliquely back to the plane of the background, to form a transition between it and the plane of the standard. We may imagine that the panel was cut through the standard, and laid against the straight line of the masonry which was then carved and cut to avoid the awkwardness of a half standard. The masonry around the east panel must have been set at the same time as the panel itself, for the lowest block on the left and the upper two blocks on the right project in front of the panel and cover the relief to some extent.

Above these reliefs runs an elaborate inpost moulding, which is too well fitted to seem to have been inserted. The moulding has the form of a cornice, with rectangular cuttings on the faces of the dentils, and eagles under the cornices. The general effect
p179 is of overelaboration.39 If the arch was ever undecorated below this cornice, it called for a more severe treatment of moulding. Also the finish of the ends near the pilasters bears on the question of the date of the cornice in relation to the present monument. The normal finish of such a return is either to continue it into the surface of a projecting member, as on the Arch of Titus, or to return the moulding on itself at right angles, as in the case of the simpler lower moulding which runs across the ends of the arch, returning on the main faces. These end mouldings of the side arches were planned for the present construction. It might be concluded that the arch once had a projecting pilaster or attached columns finished by this moulding, were it not that where it meets pilaster S2 the moulding is cut vertically without finish. This shows that it was taken from some other monument.

The words of the dedication arcum triumphis imaginemare a strong point in favor of the earlier use of the arch than the time of Constantine, for, technically, no triumph was celebrated except for victories over foreign foes, and apparently the last actual triumph was that of Diocletian in 302 A.D. It is not, however, a conclusive argument, for at the time of Constantine the word triumphis may have been used in the untechnical sense of victories, and refers to the victories, not of the past, but of the present.40 In an age of adulation, a subservient senate would not have been likely to mention on a public document in honor of an emperor the real foreign victories of his predecessors.41

To recapitulate: the main faults which offer effective argument against the Flavian theory are in brief these: the medallions are placed too high and ineffectively in uneven masonry; the pedestals under the columns form an integral part of the arch as first built, while the entablature above the columns crudely imitates in design the main cornice; both the main cornice and the impost moulding of the central arch are cut in various
p180 lengths which are joined so as to obliterate the patterns; the end of a fine cornice block was recut in the crude style to form the southwest corner; the reliefs under the main arch could not have been set after the courses of masonry which slightly overlap them.

The noble proportions of the arch and its commanding site tempt us to follow the Flavian theory. But in view of the pay irreconcilable architectural inconsistencies, it does not seem wise to adopt it.

4
The view is also that of Canina, Gli Edifizi di Roma Antica, III, p120.

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5
The article by Mr. Curtis on Roman Monumental Arches (Sup. Papers Am. School of Class. Studies in Rome, II, 55), places the introduction of free-standing columns at the time of Hadrian. He was referring however merely to existing arches.

10
Spano, op. cit., p350, states that the only similar treatment is on a double arch of Augustus, (Cohen, I, 231). Chariots drawn by elephants are on other coins of Augustus, also in profile. (Cohen, I, 229, 230). Equestrian statues in profile on a facing arch are more frequent (e.g., Cohen, I, 47, of Claudius; I, 165, of Galba).

13
Spano suggests that it represents a Janus, standing at the important junction of four roads. Foundations of a single arch of the first century are visible on the Clivus Palatinus; may this be the one which appears on the relief?

20Berl. Phil. Wochenschr., 1911, pp39, 1239. Previously, Sieveking had contended that the medallions of the south side are Flavian, and those of the north are of the time of Hadrian, Die Medallions am Konstantinsbogen, Röm. Mitth., XXVI, (1907), pp345 ff.

23
Members of the arch will be numbered from left to right, and the side indicated by N and S. See Pl. LXIII, Fig. 2.

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24
Battle Medallion N. 2 the line of the projecting base cures upward to the right, so as to suggest that the bases of the medallions at first extended farther than at present, and may have been as wide as the diameter of the tondi.

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25
The arch at Rimini has medallions in the spandrels. The arch of Trajan in the Forum of Trajan had medallions containing portraits placed over the central arch, and over the niches between the columns; Cohen, II, Trajan, 167. A Janus of Domitian had a single medallion over each arch, each bearing a figure of an eagle, Cohen, I, Domitian, 672.

28
See Plate LXIV, Fig. 2. In a few cases restorations have destroyed the original continuity of these blocks: e.g., on the east side of N. 2, N. 4, S. 2; on the west side of S. 2, 3, 4.

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29
On N. 4 there are two courses under the column plinth, but these may date from the time when the column was added.

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30
This delicate cutting suffered such general destruction on monuments that on many cornices only the semicircle and the points at the sides remain. Such is the case for example on the Arch of Trajan at Beneventum and on the Arch of Septimius Severus in the Forum, so that the publications show only points instead of the rings which once existed.

37
The date of the brickwork cannot be earlier. Miss Van Deman has assured me on this point, as shown by the photograph of the interior, Plate LXIV, Fig. 3, reproduced here by the kind permission of Dr. Ashby.

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38
See Plate LXIV, Fig. 1. Also reproduced in Brunn-Bruckmann, 580, left side.

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39
Eagles of similar type are placed between the consoles on the arch at Rimini, (Rossini, Gli Archi Trionfali, Pl. XIII), and under the console on a cornice lying in the enclosure opposite the central railroad station in Rome. Examples of rectangular cuttings on dentils are frequent on cornices from small buildings of late period and careless workmanship. A number of these show also rings between dentils, shaped like a figure 8 on its side. See especially in the Museo Chiaramonti, Abt. XI and XIII. (Amelung, Taf., 51 and 55), and a small gable now in the Colosseum near the entrance.

As is to be expected in an inserted cornice, the blocks are of varying lengths, and are fitted unevenly. It was usually cut at the side of a console, and here and there new members inserted. For example on the west side, the break at dentil 9 from the left necessitated the insertion of a new console, and a plain dentil was shoved in. Between dentils 63 and 6 of the east side is no space, and on the west, 52 is only half a dentil. Corresponding irregularities are seen above these points in the leaf patterns, as on the west side, where dentil 78 (11 from the right) is made of two half dentils, and above is only a half leaf. On the east side, there is no space between dentils 53 and 54, and the leaf above is widened. The unevenness of the work suggests two executions of the same design.

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40
The term triumphator and triumphans are repeatedly applied to Constantine in inscriptions, especially in the provinces, but also at Rome. (CIL, VIII.7006, Cirta; VIII, 2721, Lambaesis; VI, 1141, Rome.).

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41
The suggestion is made by Monaci, (Bull. Com., 1900, p114), that the phrase refers specifically to the decoration of the arch with representations of the triumphs of Trajan and of Marcus Aurelius, who mark the period of the glory of the Roman Empire, and that the phrase has no reference to the triumphs commemorated by it.

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